Coronary artery disease (CAD) is a major public health problem; current conventional imaging methods to evaluate the heart in CAD have many limitations. Magnetic resonance imaging (MRI) of the heart has great potential to improve the diagnosis and management of CAD, but it needs further development and evaluation. The long term objectives of the work proposed in this application are to produce an improved, clinically practical method for MRI evaluation of CAD and to demonstrate its utility. The specific aims are: 1) development of improved MRI perfusion imaging and analysis techniques and their integration into a comprehensive cardiac MRI examination, 2) validation of these MRI techniques in an animal model of chronic myocardial ischemia, and 3) preliminary evaluation of these techniques in a series of human cardiac patients. The technical development of cardiac imaging methods will include development of rapid perfusion imaging (through rapid imaging of the first passage of a bolus of MR contrast agent) and tissue characterization MRI techniques, and their integration with previously developed regional function MRI techniques (using tagging with spatial modulation of magnetization (SPAMM)). The corresponding image analysis programs will be developed within a program previously developed for the analysis of tagged MR images, SPAMMVU. Data visualization programs will be developed both to aid the primary interpretation of the study and to convey the results of the analysis to the referring clinician. These imaging and analysis techniques will be validated in a porcine model of chronic ischemia, including independent perfusion measurement with microspheres. Human studies will include both normal subjects and a limited series of patients with CAD; this will enable us to perform an initial evaluation of the usefulness of these MRI methods in CAD and to plan for a more definitive evaluation. The results of the MRI studies will be compared with both conventional radionuclide imaging studies and the patient's clinical course.